Feeding Postpartum Mares

Broodmares have special nutritional needs, especially right after they foal. A lactating mare’s calorie requirements are approximately double her maintenance needs for the first three months the foal is at her side and then taper until weaning. But it’s not just calories—the need for protein, vitamins, and minerals also increases during this time. Remember, the mare is providing all the nutrients for the young, growing foal but still needs to meet her own body’s needs as well.

“The need for vitamins, minerals, and quality protein containing essential amino acids such as lysine are key for keeping the diet in balance for both the mare and the foal,” said Katie Young, Ph.D., a nutritionist for Kentucky Equine Research.

Young recommends slowly ramping up the mare’s plane of nutrition just prior to foaling to help prevent weight loss after parturition. “Mares will rob their own bodies of energy and nutrients in order to provide for the foal, so a weight change is a red flag that the diet may not be meeting her needs,” she said.

Additionally, a loss of condition can potentially contribute to poor reproductive performance if the mare is to be rebred.

If a mare is losing body condition during lactation, the first step is to look at the current diet. Is she receiving good-quality forage? If the mare is on pasture, is the field lush, bare, or somewhere in between? If not lush, another forage source, such as hay, must be provided. Next, consider the concentrate. Ideally, the mare should be consuming a concentrate specifically designed for broodmares and growing foals. Check the feeding directions and make sure the product is being fed at the appropriate amount based on the mare’s body weight and stage of lactation.

Be sure the mare has a chance to consume her entire ration without competing with other mares in the field. It may be necessary to bring the mare and foal into a stall or small pen so she can eat in a stress-free environment if she is turned out in a group.

Sort out the forage and concentrate first. If the forage source is first-rate and the concentrate is fed appropriately and the mare is still losing weight, there are a few additional options. One easy way to add calories is to supplement fat. One cup of vegetable oil provides many calories, but it is recommended to top-dress this much oil over two or three feedings to encourage consumption. Commercial fat supplements such as stabilized rice bran are also an option, and are usually quite palatable and much easier to clean up if the mare does not eat it all. Another option is to add in a forage alternative, such as soaked beet pulp, to the concentrate meal. One pound (0.45 kg) of dried beet pulp shreds, roughly two dry quarts, provides a highly digestible prebiotic fiber source that supports the hindgut microbiome. Slowly adding fat or beet pulp to the diet can be helpful for weight gain and maintenance. Soaked hay cubes are also an option to encourage calorie intake.

When it comes time to wean, there is no evidence to support removing concentrate and restricting food intake to help the mare “dry up” or slow milk production. Especially if the mare has lost weight during lactation, it is not advisable to restrict her intake so severely. Instead, a gradual reduction of calories should occur as the mare enters the final weeks of lactation and she returns to a maintenance state. If the mare has been rebred, depending on the timing, weaning may coincide with the time that the diet needs to increase in nutrients and energy over maintenance (at about 5-6 months of pregnancy), so careful evaluation of breeding status, body condition, and overall dietary intake is critical to keep her properly nourished.